}
}
-static int cpufreq_add_dev_interface(struct cpufreq_policy *policy,
- struct device *dev)
+static int cpufreq_add_dev_interface(struct cpufreq_policy *policy)
{
struct freq_attr **drv_attr;
int ret = 0;
return cpufreq_set_policy(policy, &new_policy);
}
-static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy,
- unsigned int cpu, struct device *dev)
+static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu)
{
int ret = 0;
return 0;
}
-static struct cpufreq_policy *cpufreq_policy_alloc(struct device *dev)
+static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
{
+ struct device *dev = get_cpu_device(cpu);
struct cpufreq_policy *policy;
int ret;
+ if (WARN_ON(!dev))
+ return NULL;
+
policy = kzalloc(sizeof(*policy), GFP_KERNEL);
if (!policy)
return NULL;
init_completion(&policy->kobj_unregister);
INIT_WORK(&policy->update, handle_update);
- policy->cpu = dev->id;
+ policy->cpu = cpu;
/* Set this once on allocation */
- policy->kobj_cpu = dev->id;
+ policy->kobj_cpu = cpu;
return policy;
kfree(policy);
}
-/**
- * cpufreq_add_dev - add a CPU device
- *
- * Adds the cpufreq interface for a CPU device.
- *
- * The Oracle says: try running cpufreq registration/unregistration concurrently
- * with with cpu hotplugging and all hell will break loose. Tried to clean this
- * mess up, but more thorough testing is needed. - Mathieu
- */
-static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
+static int cpufreq_online(unsigned int cpu)
{
- unsigned int j, cpu = dev->id;
- int ret = -ENOMEM;
struct cpufreq_policy *policy;
+ bool new_policy;
unsigned long flags;
- bool recover_policy;
-
- pr_debug("adding CPU %u\n", cpu);
+ unsigned int j;
+ int ret;
- if (cpu_is_offline(cpu)) {
- /*
- * Only possible if we are here from the subsys_interface add
- * callback. A hotplug notifier will follow and we will handle
- * it as CPU online then. For now, just create the sysfs link,
- * unless there is no policy or the link is already present.
- */
- policy = per_cpu(cpufreq_cpu_data, cpu);
- return policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus)
- ? add_cpu_dev_symlink(policy, cpu) : 0;
- }
+ pr_debug("%s: bringing CPU%u online\n", __func__, cpu);
/* Check if this CPU already has a policy to manage it */
policy = per_cpu(cpufreq_cpu_data, cpu);
if (policy) {
WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus));
if (!policy_is_inactive(policy))
- return cpufreq_add_policy_cpu(policy, cpu, dev);
+ return cpufreq_add_policy_cpu(policy, cpu);
/* This is the only online CPU for the policy. Start over. */
- recover_policy = true;
+ new_policy = false;
down_write(&policy->rwsem);
policy->cpu = cpu;
policy->governor = NULL;
up_write(&policy->rwsem);
} else {
- recover_policy = false;
- policy = cpufreq_policy_alloc(dev);
+ new_policy = true;
+ policy = cpufreq_policy_alloc(cpu);
if (!policy)
- goto out_release_rwsem;
+ return -ENOMEM;
}
cpumask_copy(policy->cpus, cpumask_of(cpu));
down_write(&policy->rwsem);
- /* related cpus should atleast have policy->cpus */
- cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus);
-
- /* Remember which CPUs have been present at the policy creation time. */
- if (!recover_policy)
+ if (new_policy) {
+ /* related_cpus should at least include policy->cpus. */
+ cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus);
+ /* Remember CPUs present at the policy creation time. */
cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask);
+ }
/*
* affected cpus must always be the one, which are online. We aren't
*/
cpumask_and(policy->cpus, policy->cpus, cpu_online_mask);
- if (!recover_policy) {
+ if (new_policy) {
policy->user_policy.min = policy->min;
policy->user_policy.max = policy->max;
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
CPUFREQ_START, policy);
- if (!recover_policy) {
- ret = cpufreq_add_dev_interface(policy, dev);
+ if (new_policy) {
+ ret = cpufreq_add_dev_interface(policy);
if (ret)
goto out_exit_policy;
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
if (ret) {
pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n",
__func__, cpu, ret);
- goto out_remove_policy_notify;
+ /* cpufreq_policy_free() will notify based on this */
+ new_policy = false;
+ goto out_exit_policy;
}
- if (!recover_policy) {
+ if (new_policy) {
policy->user_policy.policy = policy->policy;
policy->user_policy.governor = policy->governor;
}
return 0;
-out_remove_policy_notify:
- /* cpufreq_policy_free() will notify based on this */
- recover_policy = true;
out_exit_policy:
up_write(&policy->rwsem);
if (cpufreq_driver->exit)
cpufreq_driver->exit(policy);
out_free_policy:
- cpufreq_policy_free(policy, recover_policy);
-out_release_rwsem:
+ cpufreq_policy_free(policy, !new_policy);
+ return ret;
+}
+
+/**
+ * cpufreq_add_dev - the cpufreq interface for a CPU device.
+ * @dev: CPU device.
+ * @sif: Subsystem interface structure pointer (not used)
+ */
+static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
+{
+ unsigned cpu = dev->id;
+ int ret;
+
+ dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu);
+
+ if (cpu_online(cpu)) {
+ ret = cpufreq_online(cpu);
+ } else {
+ /*
+ * A hotplug notifier will follow and we will handle it as CPU
+ * online then. For now, just create the sysfs link, unless
+ * there is no policy or the link is already present.
+ */
+ struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
+
+ ret = policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus)
+ ? add_cpu_dev_symlink(policy, cpu) : 0;
+ }
+
return ret;
}
memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo));
- if (new_policy->min > policy->max || new_policy->max < policy->min)
+ /*
+ * This check works well when we store new min/max freq attributes,
+ * because new_policy is a copy of policy with one field updated.
+ */
+ if (new_policy->min > new_policy->max)
return -EINVAL;
/* verify the cpu speed can be set within this limit */
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
CPUFREQ_ADJUST, new_policy);
- /* adjust if necessary - hardware incompatibility*/
- blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
- CPUFREQ_INCOMPATIBLE, new_policy);
-
/*
* verify the cpu speed can be set within this limit, which might be
* different to the first one
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
- struct device *dev;
- dev = get_cpu_device(cpu);
- if (dev) {
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_ONLINE:
- cpufreq_add_dev(dev, NULL);
- break;
+ switch (action & ~CPU_TASKS_FROZEN) {
+ case CPU_ONLINE:
+ cpufreq_online(cpu);
+ break;
- case CPU_DOWN_PREPARE:
- cpufreq_offline_prepare(cpu);
- break;
+ case CPU_DOWN_PREPARE:
+ cpufreq_offline_prepare(cpu);
+ break;
- case CPU_POST_DEAD:
- cpufreq_offline_finish(cpu);
- break;
+ case CPU_POST_DEAD:
+ cpufreq_offline_finish(cpu);
+ break;
- case CPU_DOWN_FAILED:
- cpufreq_add_dev(dev, NULL);
- break;
- }
+ case CPU_DOWN_FAILED:
+ cpufreq_online(cpu);
+ break;
}
return NOTIFY_OK;
}
pr_debug("trying to register driver %s\n", driver_data->name);
+ /* Protect against concurrent CPU online/offline. */
+ get_online_cpus();
+
write_lock_irqsave(&cpufreq_driver_lock, flags);
if (cpufreq_driver) {
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
- return -EEXIST;
+ ret = -EEXIST;
+ goto out;
}
cpufreq_driver = driver_data;
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
register_hotcpu_notifier(&cpufreq_cpu_notifier);
pr_debug("driver %s up and running\n", driver_data->name);
- return 0;
+out:
+ put_online_cpus();
+ return ret;
+
err_if_unreg:
subsys_interface_unregister(&cpufreq_interface);
err_boost_unreg:
write_lock_irqsave(&cpufreq_driver_lock, flags);
cpufreq_driver = NULL;
write_unlock_irqrestore(&cpufreq_driver_lock, flags);
- return ret;
+ goto out;
}
EXPORT_SYMBOL_GPL(cpufreq_register_driver);
projects / linux-2.6-microblaze.git / blobdiff